DLNA: cast subtitles

[vankasteelj]

dlnacasts3 supports subtitles but it won't work on LG WebOS. Here's a solution:

Todo:

• use mkvmerge before casting

[vankasteelj]

On LG WebOS (LG B9) - Srt casting:

• providing a path doesn't work
• providing an url doesn't work, probably needs vtt

[vankasteelj]

On LG WebOS (LG B9) - Transcoding:

• srt2vtt is somewhat working (encoding issues) but I cannot cast it

[vankasteelj]

I can't fix this, but mkvmerge could be a solution (merge video+subtitle in one mkv then cast that new file). I won't do that atm though